A number of medical procedures require the combination of illumination and visualization to enable the physician to properly carry out that procedure. Body orifices and cavities are dark, covered by opaque skin and contain deep and complex recesses. Without being able to adequately visualize the tissues, the doctor is literally “in the dark”, and the patient may be at risk. It is therefore advantageous that instruments and devices created to perform these procedures be able to provide bright illumination at their site of action, improving the experience for the doctor and enhancing the outcome for the patient.
One such procedure is laparoscopic surgery. Laparoscopic surgery is a method of minimally invasive surgery that allows surgical procedures to take place without the large incisions typically used in such surgeries. In a laparoscopic procedure, the surgeon makes a relatively small (0.5 to 1.0 cm) incision in the abdomen, usually through the navel. A trocar, a hollow tube with a gas-sealable port, is placed in the incision, and air or carbon dioxide gas is introduced into the abdominal cavity to inflate the abdomen, moving the abdominal wall away from the internal organs by means of gas pressure. One or more other small incisions are made, also using a gas-sealable port, through which various instruments—graspers, needle holders, electrocautery units, and the like—may be placed to allow the surgeon to complete the procedure. Because the overall procedure takes place within a closed abdominal cavity, the surgeon must view the work directly through a laparoscope—a surgical telescope—or indirectly on a monitor, with the image transmitted from a small camera inserted into through the trocar incision. Illumination must be provided via one or more fiberoptic probes that are usually also inserted through the trocar site.
The need for illumination to enhance visualization of the laparoscopic procedures cannot be overstressed. Often, various organs or body structures can impede the illumination of an operative site removed from the light field cast by the trocar illuminator. In those cases, the illuminator must be manipulated or reinserted to achieve sufficient illumination of the operative site to allow the procedure to continue. This may take time, and it may be difficult or impossible in some instances. Clearly, any device or strategy that would enhance the illumination of the operative site would improve the safety and efficiency of the procedure.
Current laparoscopic instruments do not provide for illumination to be directed to the operative site. They are generally made from opaque stainless steel and plastic components, and will not transmit light. Because of their necessary small diameter, it is not practical to incorporate wires and bulbs into these instruments. Also, issues of patient safety including overheating and electrical safety preclude the incorporation of bulbs and most wiring into these instruments.
Another example of a procedure that would benefit from directed illumination is foreign body removal. A common problem in pediatric medicine is the retrieval of objects from the nose and ears. Referred to in the literature as foreign bodies, they are placed in their nares or ear canals by children as part of their normal inquisitive natures and play. These foreign bodies are most often objects found close at hand to the child—stones, beads, beans, buttons, and smallish bits of organic matter such as paper or foam rubber. By the nature of the ear canal and nares, these objects tend to be rounded or oblong in shape and usually small, although occasionally the size of an object may be surprising. Other important foreign bodies are those that find their way into the ear or nose by accident, such as insects, which can cause significant anxiety and pain until they are removed.
It is generally important to remove foreign bodies when found in the ears or nose for several reasons. Foreign objects in the nose pose a danger of airway obstruction should they be inhaled through the nasopharynx into the lungs. Aspiration of a foreign body in this fashion should always be considered in the case of nasal foreign objects, and an attempt to retrieve the object or ensure its absence is imperative. Also, foreign bodies in the ear canal can cause irritation and pain. Left alone, they can erode into the wall of the ear canal where they may become embedded, requiring a surgical approach for their removal. Foreign bodies can also obstruct the ear canal, causing water retention and subsequent external otitis. For these reasons, foreign bodies found in the ear canal must also be removed.
Removing foreign bodies from either the nose or ears is not a trivial undertaking, and many approaches and devices have been used and designed to accomplish this task. The first and usually simplest approach has been to use a pair of forceps or tweezers to reach in and grasp the foreign object, and then pull it out. Both straight and offset bayonette forceps have been used for this task. While generally successful, forceps have limitations especially with round objects, such as beads. As they close, the squeezing action may force the bead deeper into the passage, much like squirting a watermelon seed between one's fingers. Thus, forceps tend to be used more for organic and irregularly shaped objects like paper and insects, and less for roundish beans and beads.
Another approach has been the use of suction, introduced by means of a narrow rigid tube, and often with a soft, formable tip. The tip is placed against the foreign object and the vacuum is applied. The tube is then withdrawn along with the foreign body. This method works best with hard, smooth objects like beads, and less well with porous materials such as paper and insects. Also, the suction tip is not lighted, so this represents a blind procedure. It is possible during the introduction of the tube into the passage (ear canal or nose) to inadvertently shove the foreign body deeper into the passage.
Another method that has been developed is the use of a balloon catheter. This is realistically only an option for the nose, due to size constraints. In this method, a balloon catheter is passed behind the foreign body in its deflated state. The balloon is then inflated with air, and the catheter is withdrawn. If successful, the balloon will push the foreign body out of the passage as it is withdrawn. Again, this tends to be a blind procedure, although the relatively larger size of the nares allows for better lighting and visualization.
In the ear, due to the narrow confines of the ear canal, the use of a balloon catheter is not practical. However, a similar approach is often used employing an ear curette to reach behind the foreign object and pull it out. While often successful, this approach sometimes leads to trauma and pain in the external ear canal. Other methods have also been utilized to remove foreign bodies. These methods, such a needles and superglue, have found their way into the medical literature but are not readily commercializable, nor are they appropriate for all cases.